My mom claims that the shells themselves helped the grounds precipitate out. She tells me that when she was a girl (in the 40s) her folks would just put a pot of water on the burner with some coffee grounds thrown in. After a few minutes they'd throw eggshells in to get the grounds to settle and then pour themselves a cup. When the inevitable company would come by, they'd just add more water and more coffee, and throw more eggshells in.

More than likely the egg shells had remnants of egg albumen (the whites), left/stuck on them. Albumen was used/works (among other things) as a fining (clarifying) agent in wine making/beer brewing & also works here.

The link above says that the conclusion that it wasn't used for coffee is based on it not being a very good coffee grinder. That doesn't seem to stop the production or sales of whirly blade grinders... ;)

More than likely the egg shells had remnants of egg albumen (the whites), left/stuck on them. Albumen was used/works (among other things) as a fining (clarifying) agent in wine making/beer brewing & also works here.

John, I know just from my memory bank & going back to when I started out homebrewing & winemaking in 1971., & reading that in the days of old time brewing & wine making in books on the subject that I have.Another olden time fining (clarifing) agent was Isinglass, which originally was the dried & pulverised swimm bladder of the Sturgeon if you can believe it. {;-)

John, I know just from my memory bank & going back to when I started out homebrewing & winemaking in 1971., & reading that in the days of old time brewing & wine making in books on the subject that I have.Another olden time fining (clarifing) agent was Isinglass, which is the dried & pulverised swimm bladder of the Sturgeon if you can believe it. {;-)

Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post

Forum Rules:No profanity, illegal acts or personal attacks will be tolerated in these discussion boards.No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum.No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek.No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum.Who Can Read The Forum? Anyone can read posts in these discussion boards.Who Can Post New Topics? Any registered CoffeeGeek member can post new topics.Who Can Post Replies? Any registered CoffeeGeek member can post replies.Can Photos be posted? Anyone can post photos in their new topics or replies.Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts.Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.